Nvidia new hotplug feature on Linux

 If you use nvidia driver for your GPU, you probably wonder why in some config, you can't hotplug your second monitor. You need to reboot to be able to use it. I found out recently with the help of chatgpt that I have been using old feature of nvidia driver all this time. The key settings are in /etc/environment.

 My previous settings:

  __NV_PRIME_RENDER_OFFLOAD=1
__GLX_VENDOR_LIBRARY_NAME=nvidia
LIBVA_DRIVER_NAME=nvidia
GTK_USE_PORTAL=1

KWIN_DRM_USE_EGL_STREAMS=1

If you can see above, I am using KWIN_DRM_USE_EGL_STREAMS=1 which means KDE is using NVIDIA’s old EGLStreams backend, which is notoriously bad at detecting new monitors in Wayland sessions. I should remove it and replace it with    GBM_BACKEND=nvidia-drm which is the modern buffer management backend for NVIDIA + Wayland that supports hotplugging of monitors.

 So i replaced it with this settings:

  
__NV_PRIME_RENDER_OFFLOAD=1
__GLX_VENDOR_LIBRARY_NAME=nvidia
LIBVA_DRIVER_NAME=nvidia
GTK_USE_PORTAL=1  
GBM_BACKEND=nvidia-drm

 I need to reboot once and testing it by unplugging and plugging it back. It works!

 That's all there is to it. Have fun! 

Installing kde-neon user edition using btrfs for root filesystem

 If you want to install KDE-Neon using btrfs as / filesystem, there is a bug that preventing it to boot successfully to console or to X or Wayland. For simplicity and laziness :)), i won't show here the errors but straight to solution or workaround.

1. Boot to live CD installer

2. Go to Konsole and edit file: sudo vi /calamares/desktop/modules/fstab.conf 

3. find word space_cache and change it to space_cache=v2

4. Start Installer and choose btrfs as filesystem for / 

It should successfully install KDE-Neon and boot to the new system successfully.

That's all there is to it. Have fun

Workaround: insync icon doesn't show up in KDE's tray in Wayland session

 This is a workaround for insync icon doesn't show up in KDE's tray in Wayland session

1. Go to System Settings

2. Click on Startup and Shutdown menu on the left

3. Clik on + Add... button to add insync and then select + Add Application...

4. Select insync in the dialog and click OK

5. insync should be listed in the Autostart 

6. Click on the insync's Properties button

7. Go o Application tab and add QT_QPA_PLATFORM=xcb in the Command section as below and then click OK button to save the settings:

8. Reboot your computer. The insync's tray icon should show up in the tray.

That's all there is to it.

Problem with KDE Look and Feel and Desktop Theme page empty in KDE System Settings (Ubuntu-based distro)

If you're experiencing empty page of KDE Look and Feel and Desktop Theme (mine from KDE Neon beta), please do these steps:

sudo apt update
sudo apt dist-upgrade
sudo apt install qml-module-org-kde-kcm

It should work.

That's all there is to it.

KDE desktop with no taskbar

Depending on the cause of this issue in your case, you may be able to fix it by editing your plasma-org.kde.plasma.desktop-appletsrc file and then performing

kquitapp plasmashell && kstart plasmashell

One cause I've run into is the buggy multimonitor functionality sometimes "losing" the taskbar from my laptop screen after I've connected to an external monitor and later disconnected (this was in plasma 5.5 or 5.6, I think). In this scenario, I've found the problem to be the lastScreen setting in the taskbar configuration. To fix this, find the section of text in plasma-org.kde.plasma.desktop-appletsrc that looks like:

[Containments][1]
activityId=
formfactor=2
immutability=1
lastScreen=1
location=4
plugin=org.kde.panel
wallpaperplugin=org.kde.image

(Some of these lines may vary in your configuration. In mine, this section was only a dozen lines down in the file, but I have no idea how much that may vary.)

Setting lastscreen=0 fixed the problem for me. I assume that 0 represents my laptop screen, and 1 is the external monitor.

If in doubt, you can always perform the procedure in jozxyqk's answer, and compare the newly generated plasma-org.kde.plasma.desktop-appletsrc with your saved plasma-org.kde.plasma.desktop-appletsrc.bak before restoring an edited version of your saved copy.

How to disable ctl+alt+backspace key from killing your X server in KDE?

I recently accidentally pressed ctrl+alt+backspace key combination. It killed my X server. To prevent it from happening again and to protect your unsaved works, you have to disable this key combination. For KDE 4.x users, below are the steps:

Open the settings page:
Menu --> Applications --> Settings --> System Settings

Open the Input Devices:

Clik on Keyboard and the Advanced tab and click on the Configure keyboard options checkbox:

Find Key sequence to kill the X server from the list and untick the check box for Ctrl + Alt + Backspace

And then click the Apply button to save the settings.

That is all there is to it. Have fun!

changing manually wireless connection to be controlled by knetworkmanager

knetworkmanager is a Network Manager for KDE4. It is hated or liked by users and usually not in between. I personally like it although it has its fair share of bugs. But I like Mandriva's net_applet more. It is stable and more reliable. It is prefered by many Mandriva users. However, if you are stuck with recent problems (bug?) of perl in Mandriva Cooker like me, you are forced to use command line of wpa_supplicant or iwconfig or using gui application like knetworkmanager. 

In Mandriva, you can change which network manager control the wireless connection by changing the option in net_applet or you can manually change in file /etc/sysconfig/network-scripts/ifcfg-wlan0. If you want knetworkmanager in control of it, you just have to change this line to yes:

NM_CONTROLLED=yes

KDE 4.5 stable released

KDE 4.5 stable released. For Mandriva users, please add KDE 4.5 repo (as root):

64-bit:

urpmaddmedia kde-4.5 http://ftp.twaren.net/Unix/X/KDE/stable/4.5.0/Mandriva/2010.1/x86_64/

32-bit:

urpmi.addmedia kde-4.5 http://ftp.twaren.net/Unix/X/KDE/stable/4.5.0/Mandriva/2010.1/i586/

You may want to remove the old KDE repo first.

or if you prefer KDE server as your repo thusly:

64-bit:

urpmi.addmedia kde-4.5 ftp://ftp.kde.org/pub/kde/stable/4.5.0/Mandriva/2010.1/x86_64

32-bit:

urpmi.addmedia kde-4.5 ftp://ftp.kde.org/pub/kde/stable/4.5.0/Mandriva/2010.1/i586

Have fun!

KDE 4.5 RC3 released for Mandriva

KDE 4.5 Release Candidate 3 is released for Mandriva users. The final version will be available next week. This last RC is intended for verifying no showstoppers will creep into the final release of 4.5.0. It will also interest those who want an early look at what is coming to their desktops and netbooks this summer.

To install, please add KDE 4.5RC3 repo first:

urpmi.addmedia kde-4.5rc3 http://ftp.twaren.net/Unix/X/KDE/unstable/4.4.95/Mandriva/2010.1/x86_64/

I use above mirror for my repo for faster access. You may want to use main KDE server for your repo thus:

urpmi.addmedia kde-4.5rc3 ftp://ftp.kde.org/pub/kde/unstable/4.4.95/Mandriva/2010.1/x86_64/

For x86 (32-bit) users, please change the path x86_64 to i586. Then run urpmi --auto-select to update your KDE packages.

Have fun with your new KDE!

KDE 4.3 released

KDE 4.3 (Caizen) was released on 4th August 2009. KDE 4.3 is the latest major release in the KDE 4 series, delivering a more polished user experience. The KDE community has fixed over 10,000 bugs and implemented almost 2,000 feature requests in the last 6 months. Close to 63,000 changes were checked in by a little under 700 contributors. Read on for an overview of the changes in the KDE 4.3 Desktop Workspace, Application Suites and the KDE 4.3 Development Platform.



More info can be read on kde.org

KDE 4.3 Beta 1 released for testing

KDE.org announced the release of KDE 4.3 Beta 1 for testing. This is the first review of the 3rd iteration of KDE 4 desktop.

Some highlights of this beta release are:
1.Integration of PolicyKit and Geolocation services
2.More usable Run command pop-up (press alt+F2 to activate)
3. Many new and improved add-ons for plasma
4. Many bugfixes and improvements across all applications and more integration of features coming with the KDE 4 platform
5. New tree mode in System Settings

and many more. For a complete list of changes, you can browse subversion log.

Reference
http://kde.org/announcements/announce-4.3-beta1.php

KDE 4.0 released (at last!)

The much-awaited KDE 4.0 has been released on Friday 11 Jan 2007.

From the announcement page:

The KDE Community is thrilled to announce the immediate availability of KDE 4.0. This significant release marks both the end of the long and intensive development cycle leading up to KDE 4.0 and the beginning of the KDE 4 era.

The KDE 4 Libraries have seen major improvements in almost all areas. The Phonon multimedia framework provides platform independent multimedia support to all KDE applications, the Solid hardware integration framework makes interacting with (removable) devices easier and provides tools for better power management.

The KDE 4 Desktop has gained some major new capabilities. The Plasma desktop shell offers a new desktop interface, including panel, menu and widgets on the desktop as well as a dashboard function. KWin, the KDE Window manager, now supports advanced graphical effects to ease interaction with your windows.

Lots of KDE Applications have seen improvements as well. Visual updates through vector-based artwork, changes in the underlying libraries, user interface enhancements, new features, even new applications -- you name it, KDE 4.0 has it. Okular, the new document viewer and Dolphin, the new file manager are only two applications that leverage KDE 4.0's new technologies.

To install KDE 4.0, the experimental branch must be enabled. Add the following to /etc/apt/sources.list, then update APT.

deb http://ftp.debian.org/debian/ experimental main non-free contrib

deb-src http://ftp.debian.org/debian/ experimental main non-free contrib

APT will not install packages from experimental unless specifically requested. To install a package from experimental, run the command:

aptitude -t experimental install kdebase kdebase-workspace


or

apt-get -t experimental install kdebase kdebase-workspace


Those are the basic packages. For other packages, please look here.

Have fun!